Juniper EX4100 Hardware Manual page 76

Fan Module Status
Each fan module has a status LED on it that indicates the status of the fan module.
67 describes the LED.
Figure 54: Fan Module Status LED
1 Fan module status LED
—
Table 12: Fan Module Status LED
State
Green
Unlit
Description
The fan module is functioning normally.
Indicates one of the following:
•
The fan module is not installed.
•
The fan module is not functioning normally.
•
The airflow direction of the fan module does not match the airflow direction of
other components.
Table 12 on page
67